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Database-level roles

Applies to: SQL Server Azure SQL Database Azure SQL Managed Instance Azure Synapse Analytics Analytics Platform System (PDW)

To easily manage the permissions in your databases, SQL Server provides several roles that are security principals that group other principals. They are like groups in the Windows operating system. Database-level roles are database-wide in their permissions scope.

To add and remove users to a database role, use the ADD MEMBER and DROP MEMBER options of the ALTER ROLE statement. Analytics Platform System (PDW) and Azure Synapse Analytics doesn't support the use of ALTER ROLE. Use the older sp_addrolemember and sp_droprolemember procedures instead.

There are two types of database-level roles: fixed database roles that are predefined in the database and user-defined database roles that you can create.

Fixed database roles are defined at the database-level and exist in each database. Members of the db_owner database role can manage fixed database role membership. There are also some special-purpose database roles in the msdb database.

You can add any database account and other SQL Server roles into database-level roles.

Tip

Don't add user-defined database roles as members of fixed roles. This could enable unintended privilege escalation.

The permissions of user-defined database roles can be customized by using the GRANT, DENY, and REVOKE statements. For more information, see Permissions (Database Engine).

For a list of all the permissions, see the Database Engine Permissions poster. Server-level permissions can't be granted to database roles. Logins and other server-level principals (such as server roles) can't be added to database roles. For server-level security in SQL Server, use server roles instead. Server-level permissions can't be granted through roles in Azure SQL Database and Azure Synapse Analytics.

Fixed database roles

The following table shows the fixed database roles and their capabilities. These roles exist in all databases. Except for the public database role, the permissions assigned to the fixed database roles can't be changed.

Fixed database role name Description
db_owner Members of the db_owner fixed database role can perform all configuration and maintenance activities on the database, and can also DROP the database in SQL Server. (In SQL Database and Azure Synapse, some maintenance activities require server-level permissions and can't be performed by db_owners.)
db_securityadmin Members of the db_securityadmin fixed database role can modify role membership for custom roles only and manage permissions. Members of this role can potentially elevate their privileges and their actions should be monitored.
db_accessadmin Members of the db_accessadmin fixed database role can add or remove access to the database for Windows logins, Windows groups, and SQL Server logins.
db_backupoperator Members of the db_backupoperator fixed database role can back up the database.
db_ddladmin Members of the db_ddladmin fixed database role can run any Data Definition Language (DDL) command in a database. Members of this role can potentially elevate their privileges by manipulating code that might get executed under high privileges and their actions should be monitored.
db_datawriter Members of the db_datawriter fixed database role can add, delete, or change data in all user tables. In most use cases, this role is combined with db_datareader membership to allow reading the data that is to be modified.
db_datareader Members of the db_datareader fixed database role can read all data from all user tables and views. User objects can exist in any schema except sys and INFORMATION_SCHEMA.
db_denydatawriter Members of the db_denydatawriter fixed database role can't add, modify, or delete any data in the user tables within a database.
db_denydatareader Members of the db_denydatareader fixed database role can't read any data from the user tables and views within a database.

The permissions assigned to the fixed database roles can't be changed. The following figure shows the permissions assigned to the fixed database roles:

Diagram of fixed database role permissions.

Special roles for Azure SQL Database and Azure Synapse

These database roles exist only in the virtual master database. Their permissions are restricted to actions performed in master. Only database users in master can be added to these roles. Logins can't be added to these roles, but users can be created based on logins and then those users can be added to the roles. Contained database users in master can also be added to these roles. However, contained database users added to the dbmanager role in master can't be used to create new databases.

Role name Description
dbmanager Can create and delete databases. A member of the dbmanager role that creates a database, becomes the owner of that database, which allows that user to connect to that database as the dbo user. The dbo user has all database permissions in the database. Members of the dbmanager role don't necessarily have permission to access databases that they don't own.
db_exporter Members of the db_exporter fixed database role can perform all data export activities. Permissions granted via this role are CREATE TABLE, ALTER ANY SCHEMA, ALTER ANY EXTERNAL DATA SOURCE, ALTER ANY EXTERNAL FILE FORMAT.

Applies to: Azure Synapse Analytics dedicated SQL pools (formerly SQL DW)
loginmanager Can create and delete logins in the virtual master database.

Note

The server-level principal and the Microsoft Entra administrator (if configured) have all permissions in SQL Database and Azure Synapse Analytics without needing to be members of any roles. For more information, see Authorize database access to SQL Database, SQL Managed Instance, and Azure Synapse Analytics.

Some database roles aren't applicable to Azure SQL or Azure Synapse:

  • db_backupoperator isn't applicable in Azure SQL Database (not Azure SQL Managed Instance) and Azure Synapse Analytics serverless pool because backup and restore T-SQL commands aren't available.

  • db_datawriter and db_denydatawriter aren't applicable to Azure Synapse Analytics serverless because it just reads external data.

Roles in msdb database

The msdb database contains the special-purpose roles that are shown in the following table.

msdb role name Description
db_ssisadmin
db_ssisoperator
db_ssisltduser
Members of these database roles can administer and use SSIS. Instances of SQL Server that are upgraded from an earlier version might contain an older version of the role that was named using Data Transformation Services (DTS) instead of SSIS. For more information, see Integration Services Roles (SSIS Service).
dc_admin
dc_operator
dc_proxy
Members of these database roles can administer and use the data collector. For more information, see Data collection.
PolicyAdministratorRole Members of the db_ PolicyAdministratorRole database role can perform all configuration and maintenance activities on Policy-Based Management policies and conditions. For more information, see Administer Servers by Using Policy-Based Management.
ServerGroupAdministratorRole
ServerGroupReaderRole
Members of these database roles can administer and use registered server groups.
dbm_monitor Created in the msdb database when the first database is registered in Database Mirroring Monitor. The dbm_monitor role has no members until a system administrator assigns users to the role.

Members of the db_ssisadmin role and the dc_admin role might be able to elevate their privileges to sysadmin. This elevation of privilege can occur because these roles can modify Integration Services packages and Integration Services packages can be executed by SQL Server using the sysadmin security context of SQL Server Agent. To guard against this elevation of privilege when running maintenance plans, data collection sets, and other Integration Services packages, configure SQL Server Agent jobs that run packages to use a proxy account with limited privileges or only add sysadmin members to the db_ssisadmin and dc_admin roles.

Work with database-level roles

The following table explains the commands, views, and functions for working with database-level roles.

Feature Type Description
sp_helpdbfixedrole Metadata Returns a list of the fixed database roles.
sp_dbfixedrolepermission Metadata Displays the permissions of a fixed database role.
sp_helprole Metadata Returns information about the roles in the current database.
sp_helprolemember Metadata Returns information about the members of a role in the current database.
sys.database_role_members Metadata Returns one row for each member of each database role.
IS_MEMBER Metadata Indicates whether the current user is a member of the specified Microsoft Windows group, Microsoft Entra group, or Microsoft SQL Server database role.
CREATE ROLE Command Creates a new database role in the current database.
ALTER ROLE Command Changes the name or membership of a database role.
DROP ROLE Command Removes a role from the database.
sp_addrole Command Creates a new database role in the current database.
sp_droprole Command Removes a database role from the current database.
sp_addrolemember Command Adds a database user, database role, Windows login, or Windows group to a database role in the current database. All platforms except Analytics Platform System (PDW) and Azure Synapse should use ALTER ROLE instead.
sp_droprolemember Command Removes a security account from a SQL Server role in the current database. All platforms except Analytics Platform System (PDW) and Azure Synapse should use ALTER ROLE instead.
GRANT Permissions Adds permission to a role.
DENY Permissions Denies a permission to a role.
REVOKE Permissions Removes previously granted or denied permissions.

Public database role

Every database user belongs to the public database role. When a user hasn't been granted or denied specific permissions on a securable object, the user inherits the permissions granted to public on that object. Database users can't be removed from the public role.

Examples

The examples in this section show how to work with database-level roles.

A. Add a User to a database-level role

The following example adds the User 'Ben' to the fixed database-level role db_datareader.

ALTER ROLE db_datareader ADD MEMBER Ben;
GO

B. List all database principals that are members of a database-level role

The following statement returns all members of any database role.

SELECT roles.principal_id AS RolePrincipalID,
    roles.name AS RolePrincipalName,
    database_role_members.member_principal_id AS MemberPrincipalID,
    members.name AS MemberPrincipalName
FROM sys.database_role_members AS database_role_members
INNER JOIN sys.database_principals AS roles
    ON database_role_members.role_principal_id = roles.principal_id
INNER JOIN sys.database_principals AS members
    ON database_role_members.member_principal_id = members.principal_id;
GO